纤维状碱式碳酸铝铵的固相合成及其热解的自粉碎特征

Synthesis of Fibrous Ammonium Aluminium Carbonate Hydroxide via Solid State Reaction and Its Self-broken Characters on Pyrolysis

在钠、镁离子的调控下,用室温固相反应法合成得到了纤维状的碱式碳酸铝铵(AACH),产物结晶度较好,长度约20～30μm。该纤维状的AACH在高温裂解得到的氧化铝仅为60nm左右的晶体。在长度上,氧化铝只是前驱体纤维状AACH的五百分之一左右,说明AACH在高温裂解时经历了猛烈的"爆炸",自行粉碎成纳米级的小碎块,碎块完全分解后得到60nm左右的氧化铝晶体。这种自粉碎的良好特征,使其成为制备纳米氧化铝的一个重要的前驱体。

Fibrous ammonium aluminium carbonate hydroxide (AACH)was synthesized via solid state reaction at room temperature controlled with sodium and magnesium ions.The fibrous AACH is crystals about 20～30 μm in length with good crystallinity.The particle size of alumina crystals obtained by pyrolysis of AACH was 60 nm,only five hundredth the length of the precursor,indicating that AACH undergoes fierce “blast” during pyrolysis,changing by self-shattering into nano-shivers.Nanocrystals of alumina about 60 nm in lenghth were got after the nano-shivers were completely pyrolyzed.It is the outstanding character of self-shattering during pyrolysis that makes AACH a key precursor for preparing nano-alumina.